Dr. Cameron (archive footage)
Prof. Lampini
Egyptian Ambassador (uncredited)
Father Robert Stuart
The Voice
Judge Mackenzie
H.G. Danziger
Dubocage
Dr. Fortescue
The Judge
Constable of Clervaux
The Viceroy
Otto Dagoff
Palanth, the High Priest
Doc Hugo Robbin
Marquis De Carvajal
Paul Stertorius
Father Donnard
Officer H.R. Barrett
Craxton
Dr. Josef Van Ee
Mr. Mallam
Prof. Andrew Forbes
Dr. Pavel Storasky
Detective Geddes
Bey of Aribajan
Jelke
Horadef
King aka The Great Movel
(uncredited)
Leo Grainger
Prof. Bruno Lampini
Frank Swift
Fahrenburg
Ape Man
Andoheb, High Priest of Arkan
Nicholas
Tony Rocco
Dr. Alfred Morris
Mr. Crepitude
Amos Bradford
Lloyd Clayton / Elwyn Clayton
Heinrich Hinckel aka Richard Stanley
Lord Denby
Andoheb
Dr. Robert Renault
Peter van Hoost
Lorenzo Cameron
Dr. Hugo Streger
Dr. Edwin L. Jannery
Webster
Defense Attorney
Dr. Jeris
Dr. Parry
Abbadi
Prison Governor
Professor Andoheb
Vicomte Ribaud
Procurator
Lawyer Crosby
James K. Spaulding
Professor Moriarty
Dr. Luis Virgo
Arnold Trist
Dr. Cardigan
Rolf Alferson
Prime Minister
Dr. Waxton
Governor of Conciergerie (uncredited)
Otto Brockler
James 'Jim' Hampstead
Prefect of Police
General Maroff
Secret Service Chief
Count Armalia
Dr. LaFarge
Woodley
Inspector Jefferson
Dr. Bierd
Sir Charles Arthur Russell
Dr. Adolph Kammer
Crowley Bascomb
The Colonel's Butler
Dr. Pyke
Officer of the Firing Squad
Convict
Proprietor of the Maison de Paris
Hotel Manager
Inspector Hull
Man from Reclamation Agent
Revered Mayne
Fauntley
James Renton
Squire
Lord Dore
Prosecutor (uncredited)
Jacques Marie Eugène Godefroy Cavaignac